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A new capitosaur from the Middle of Spain and the relationships within the Capitosauria

JOSEP FORTUNY, ÀNGEL GALOBART, and CARLES DE SANTISTEBAN

Fortuny, J., Galobart, À., and De Santisteban, C. 2011. A new capitosaur from the of Spain and the rela− tionships within the Capitosauria. Acta Palaeontologica Polonica 56 (3): 553–566.

Capitosaurs were the largest and homogeneous group of Triassic temnospondyl with cosmopolitan distribu− tion. However, their interrelationships are debated. The first capitosaur cranial remains found in the Iberian Peninsula were assigned to ; herein, a re−description of this material, together with information on other remains re− covered from the same site, enables us to classify them as a new : Calmasuchus acri gen. et sp. nov. (Amphibia: ) from the early−to−middle (early Middle Triassic). This capitosaur had a combination of plesiomorphic and non−plesiomorphic characters, such as posterolaterally directed tabular horns, paired anterior palatal vacuities, and unique morphology of the lower jaw. By cladistic analysis, we propose a new phylogeny for the monophyletic capitosaurs. In the analysis, Capitosauria is supported by seven synapomorphies. Wetlugasaurus is the most member of the . The score of the Russian taxon Vladlenosaurus alexeyevi resulted in a clade including Odenwaldia and the latter taxa. The Madagascarian Edingerella is the sister taxon of Watsonisuchus. Finally, Calma− suchus acri, the new taxon described here, appears as a more derived form than Parotosuchus. The new genus is the sister taxon of the –Tatrasuchus and Eryosuchus– .

Key words: Temnospondyli, Capitosauria, Mastodonsauroidea, phylogeny, computed tomographic scanning, Anisian, Triassic, Spain.

Josep Fortuny [[email protected]] and Ángel Galobart [[email protected]], Institut Català de Paleontologia, Universitat Autònoma de Barcelona, Edifici ICP, Campus de Bellaterra s/n, 08193 Cerdanyola del Vallès, Barcelona, Spain; Carles de Santisteban [[email protected]], Departament de Geologia, Universitat de València, C/o Dr. Moliner 50, 46100 Burjassot, València, Spain.

Received 12 March 2010, accepted 20 December 2010, available online 29 December 2010.

Introduction The first revision of the group (Welles and Cosgriff 1965) focused on the evolution of the otic notch (open in primitive Capitosaurs constituted one of the most abundant groups of forms and closed in derived forms) in an attempt to establish Triassic temnospondyl amphibians. Despite their cosmo− the of the “Capitosauridae”. The revision by Ochev politan distribution, records in the Iberian Peninsula (1966) was markedly different: a large number of genera and are scarce, with only three reported sites: Rocha da Pena, were recognised by using the shape of the tabular horn Portugal (Witzmann and Gassner 2008); and La Mora and as a criterion for determining taxonomic relationships. The Riera de Sant Jaume, Spain (Gaete et al. 1993; JF unpub− most recent revisions (Schoch 2000; Damiani 2001; Schoch lished data). 2008; Maganuco et al. 2009) demonstrate that the evolution of The wide distribution of temnospondyls, especially capito− the group involves more cranial characters than those regarded saurs, has been used in biostratigraphy (Cosgriff and Defauw previously. 1987) to correlate Triassic tetrapod faunas (Lucas 1998). On the other hand, recent papers include new descriptions These faunas are well known in the Eastern European plat− of old and new specimens recovered from the Central Euro− form (e.g., Ochev and Shishkin 1989; Shishkin and Ochev pean Basin, providing crucial information to understand the 1994) and Beafourt Group of South (Karoo Basin) evolution of the clade; especially, capitosaur remains have (e.g., Hancox et al. 1995; Shishkin et al. 1995; Damiani 2004). been described in detail (Maryańska and Shishkin 1996; However, the phylogenetic relationships of capitosaurs have Schoch 1997, 1999; Sulej and Majer 2005; Shishkin and remained controversial since the first discoveries, even with Sulej 2009). The first capitosaur cranial remains recovered in the more recent studies (e.g., Watson 1962; Welles and Cros− Spain were assigned to Parotosuchus (Gaete et al. 1993, griff 1965; Ochev 1966; Schoch 2000; Schoch and Milner 1994, 1996). Here, we present a revised description of the 2000; Damiani 2001; Steyer 2003; Schoch 2008; Maganuco et original and new materials, enabling us to establish a new ge− al. 2009). nus—Calmasuchus acri gen. et sp. nov. (Amphibia: Temno−

Acta Palaeontol. Pol. 56 (3): 553–566, 2011 http://dx.doi.org/10.4202/app.2010.0025 554 ACTA PALAEONTOLOGICA POLONICA 56 (3), 2011

Facies: A D

C S4

A E

D B D A D El Muntanyá C S3 Collformic

cross stratifications SERRA DE PICAMENA C stream mark

A E D

C S2 Cenozoic Aiguafreda la Calma D B Buntsandstein Facies D E Lower Facies B D S1 Middle Muschelkalk Facies A D Upper Muschelkalk Facies Tagamanent N 1m Paleozoic Paleozoic 1:50.000 0 0.75 1.50 km Fig. 1. Geographic and geologic location of the capitosaur Calmasuchus acri gen. et sp. nov. from the Anisian at the La Mora site, Spain, with a stratigraphic cross−section containing the vertebrate locality (arrow). See text for facies interpretation. spondyli)—and providing new data to resolve the evolution continental deposits (Calvet and Marzo 1994). These materi− of the group. In this regard, new data acquired by computed als are derived from the erosion of the Iberian Massif and tomography, including complete skull reconstruction of this they show thickness increment from northeast (145 m) to taxon, have been added to the previous information obtained southwest (310 m). by mechanical preparation of the matrix. Cladistic analysis The sedimentary deposits of this sub−basin are mainly including the new taxa performed by using an updated ver− composed of sandstone, mudstone, and red clay (Areniscas y sion of the previous matrix of Damiani (2001) for the group Lutitas del Figaró unit); these materials are interpreted as flu− has enabled us to propose a new phylogeny. vial deposits and distributed from northwest−northeast to southeast−southwest (Calvet and Marzo 1994). Institutional abbreviations.—IPS, Institut Català de Paleonto− At the La Mora site, the Buntsandstein facies deposits be− logia, Sabadell, Spain; MB, Museum für Naturkunde, Berlin, long to the lower part of the Areniscas y Lutitas del Figaró Germany; MNHN, Muséum National d'Histoire Naturelle, unit. This unit is unconformable on Paleozoic metamorphic Paris, France; PIN, Paleontological Institute of the Russian rocks. The section is 25 m thick and is composed of intercala− Academy of Sciences, Moscow, Russia. tions of red clay, mudstone, and sandstone in four sedimen− tary sequences with five different facies bound by caliche− type palaeosols (Fig. 1). The materials are interpreted as in− Geological setting filling of a channel body with an erosional base and a topping plane. Facies A represents the first deposits that formed the The Triassic outcrops of the La Mora site (Catalonia, Spain, base of the level and deposits B are enclosed by the margin of northeast of the Iberian Peninsula) belong to the Montseny− the channel. Both are interpreted as point bars. In relation to Llobregat domain (Calvet and Marzo 1994) of the Cata− these point bars, the sandstone from facies C fills the central lonian basin. This palaeogeographic unit has been identified part of the channel and its equivalent to the lower part of the as one of the eastern−most sub−basins of the Iberian plate. deposits of the point bar. Facies C yields the vertebrate local− The Buntsandstein facies in this area (Fig. 1) is formed by ity. The clay and silt from facies D constitute the final infill− FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS 555

50 mm

Fig. 2. Computed tomographic reconstruction of the capitosaur Calmasuchus acri gen. et sp. nov. from the Anisian at the La Mora site, Spain, in dorsal (A), ventral (B), lateral (C), and occipital (D) views. ing of the abandoned fluvial channel and extend beyond the of this facies and the ammonite Paraceratites fauna is lo− boundary of the channel as flood−plain deposits. In facies E, cated in the middle part of the lower Muschelkalk facies (see the sediments show a concentration of calcium carbonate Márquez−Aliaga et al. 2000; Dinarès−Turell et al. 2005 for nodules. further details). All these data restrict the La Mora site to an The age of the Areniscas y Lutitas del Figaró unit remains Aegean−to−middle Pelsonian age (early−to−middle Anisian). uncertain. The first palynological work in this Buntsandstein facies (Solé de Porta et al. 1987) dated the unit as Anisian. A recent palaeomagnetostratigraphic study excludes the possi− Materials and methods bility of an stage (Dinarès−Turell et al. 2005) and biostratigraphic analysis of the overlying lower Muschelkalk The La Mora site was discovered in 1989 by local hikers facies indicates an age of middle−to−upper Pelsonian to upper Emili Ramon and Pere Font. A year later, palaeontological Illyrian (middle−to−upper Anisian), on the basis of the pres− fieldwork was undertaken by the Institut de Paleontologia de ence of the conodonts Paragondolella bulgarica, P. han− Sabadell (Spain), extracting hundreds of cranial and post− bulogi, P. bifurcata, Neogondolella constricta, N. cornuta, cranial bones. Most of these bones were identified as belong− N. excentrica, and N. basisymetrica. In addition, the brachio− ing to capitosaurs. Other elements were postcranial elements pod Spiriferina (Mentzelia) mentzeli is recognised at the base of archosauromorphs and cranial remains of procolopho−

http://dx.doi.org/10.4202/app.2010.0025 556 ACTA PALAEONTOLOGICA POLONICA 56 (3), 2011 noids noted in previous studies and currently under study y Lutitas del Figaro unit, and dated as early−to−middle Anisian (Middle (Gaete et al. 1993, 1994, 1996; JF unpublished data). In addi− Triassic). tion, tetrapod ichnites were recovered close to the site, in− Diagnosis.—Distinguished from all other capitosaurs by a cluding the ichnogenera Rhynchosauroides, , combination of the following characters: posterolaterally di− and Synaptichnium (see Calzada 1987 for further details). rected tabular horns, orbital margins flush with the plane of The hard matrix and high density of bones (often in con− the skull, the postorbital and prefrontal near each other by tact) hindered their preparation for a long time and made de− thin projections, paired anterior palatal vacuity, long choanal scription of the osteology of these materials and identifica− outline, the frontal enters the medial border of the orbit, pres− tion of diagnostic characters difficult (Gaete et al. 1994). ence of a transversely oriented transvomerine tooth row, Nevertheless, after several years of mechanical preparation, cultriform process of the parasphenoid extends beyond the cranial remains were sufficiently prepared for description. anterior border of the interpterygoid vacuities, absence of the Moreover, computed tomographic scans were performed to denticle field in the pterygoid and parasphenoid, elongated understand the morphology of some areas better, and as a and well developed postglenoid area. useful tool to enable skull reconstruction by using cranial re− Preservation.—Fossil bone remains from the La Mora site mains (Fig. 2). This reconstruction shows the mandible and are well preserved despite the hard matrix that wraps parts of the major part of the skull roof and palatal regions. All the the bones and the action of sedimentary compaction and tec− cranial remains were scanned by multidetector computer to− tonic stress that slightly crushed some anatomical structures, mography (Sensations 16; Siemens) at Hospital Universitari making assessment of some cranial characters difficult. To Mútua Terrassa (Barcelona, Spain). Each cranial specimen resolve this problem, other cranial fragments are described was scanned at 140 kV and 220 mA with an output of 512 × when the characters are poorly or not preserved in the holo− 512 pixels per slice, with an interslice space of 0.2 mm, and type. Here, we focus on the study of some incomplete skulls processed by using the Mimics software (Materialise, recovered from the La Mora site. All the cranial remains dis− Leuven, Belgium), obtaining an almost complete skull re− play well−fused sutures, indicating that they belong to adult construction from the partial fossil material. . The partial cranial fragments recovered and the computed tomographic reconstruction allowed description of the skull. Systematic palaeontology Description Temnospondyli Zittel 1890 (sensu Milner 1990) Skull roof.—The skull roof is nearly complete in IPS−37401 Zittel 1890 (emend. Fraas 1889) (LM−83) (Fig. 3). The length of the skull roof, as preserved, is 30.9 cm from the posterior margin of the skull to the external Capitosauria Yates and Warren 2000 (emend. nares (anterior margin). The tip of the snout anterior to the ex− Damiani and Yates 2003) ternal nares is not preserved in the dorsal view. The postero− Genus Calmasuchus nov. lateral region of the skull roof is incomplete in IPS−37401 Etymology: After Pla de la Calma, the Catalan toponym for the type lo− (LM−83), but it is well preserved in IPS−37401 (LM−63, L, and cality. M1) (Figs. 4, 6). The sutures of the skull elements in IPS− Type and only known species: Calmasuchus acri sp. nov.; see below. 37401 (LM−83) are firmly fused and discernible. The bone or− namentation is well developed and corresponds to the typical Diagnosis.—Same as for the type and only species. temnospondyl pitted sculpture pattern. In the dorsal view, the Stratigraphic and geographic range.—Early–middle Anisian, overall shape of the skull roof displays a convex snout. The Tagamanent, Barcelona, Spain. tabular sutures the squamosal at the level of the anterior mar− Calmasuchus acri sp. nov. gin of the otic notch. The tabular horns are posterolaterally di− rected where the apex of the horn is in close proximity to the Figs. 2–6. squamosal posteriorly, without suturing it posteriorly. The 1993 Parotosuchus sp.; Gaete et al. 1993. posterior tip of the tabular is nearly equally expanded medio− Etymology: From the Latin acre, defined as hard or strong and referring laterally but only slightly expanded anterodistally. The tabular to the hardness of the matrix that surrounds the and makes prepa− horns are complete and well preserved in IPS−37401 (L and ration of the material difficult. M1). IPS−37401 (LM−63) preserves the tabular–squamosal Type material: Holotype: IPS−37401 (LM−83) has a partial skull roof and tabular–supratemporal sutures. In this fragment, the tabu− and palate (Fig. 3). Paratypes: IPS−37401 (LM−63, LM−101, L, and M1) consists of skull fragments and IPS−42407 (LM−4) is a complete hemi− lar horns are not completely preserved, preventing description mandible (Figs. 4, 5). of its postparietal–tabular margin, which shows an unpre− Type locality: All the specimens were collected from the La Mora site of served suture. On the other hand, Calmasuchus acri lacks the the Catalonian basin, Barcelona, Spain. All were collected by Àngel long processus lateralis present in the tabular of some capito− Galobart, Rodrigo Gaete, and Xavier Ros in 1990. saurs. The posterior margin of the squamosal is slightly con− Type horizon: Catalonian basin, Catalan Coastal Ranges, Buntsandstein vex dorsally, with a narrow falciform crest. facies from the Montseny−Llobregat Domain, included in the Areniscas The parietal is longer than the supratemporal, which is FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS 557

nares

nasal lacrimal

supraorbital sulcus

prefrontal jugal frontal jugal sulcus

postorbital

postfrontal pineal foramen parietal

50 mm anterior palatal vacuity

fang tooth choana vomer

palatine

palatine cultriform process

ectopterygoid interpterygoid pterygoid vacuity tooth

pterygoid

papasphenoid

Fig. 3. Remains of the capitosaur Calmasuchus acri gen. et sp. nov. IPS−37401 (LM−83) from the Anisian at the La Mora site, Spain, in dorsal (A, B) and ventral (C, D) views. Photographs (A, C) and explanatory drawings (B, D). slightly longer than the postparietal. The supratemporal is 30.3 mm in width. The orbital margin lies in the same plane excluded from the otic notch. The frontal enters the medial of the skull roof. Apart from this, the interorbital area is flat− border of orbit. The morphology of the orbit is slightly sub− tened and moderately broad (55.2 mm in width) in compari− circular, and in IPS−37401 (LM−63), it is 35 mm in length and son with other capitosaurs (e.g., Stanocephalosaurus pro−

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parietal jugal pineal orbit temporal foramen sulcus supratemporal postorbital postparietal jugal sulcus squamosal tabular quadratojugal

50 mm

vertebra transvomerine tooth anterior palatal vacuity neural arch fang vertebra choana

vomer tooth vertebra rib parasphenoid exoccipital pterygoid occipital condyle 50 mm jugal

quadrate quadratojugal

slab L

slab M1 supratemporal tabular postfrontal

postparietal vertebra parietal jugal

femur 50 mm

Fig. 4. Photographs and drawings of paratypes of the capitosaur Calmasuchus acri gen. et sp. nov. from the Anisian at the La Mora site, Spain. A. Cranial re− mains IPS−37401 (LM−63), in dorsal (A1,A2) and ventral (A3,A4) views. B. Palatal fragment IPS−37401 (LM−101), in dorsal (B1,B2) view. C. Posterior skull roof fragments of IPS−37401 (L and M1), in dorsal (C1,C2) view. Note that fragments L and M1 are in contact. Photographs (A1,A3,B1,C1) and ex− planatory drawings (A2, A4, B2, C2). nus) with narrow interorbital distance. The postorbital is Sensory sulci.—The lateral line sensory canals are discontin− moderately expanded anterolaterally because it occupies less uous. The supraorbital sensory canal passes across the poste− than half of the orbital border. The postorbital and prefrontal rior section of the suture between the lacrimal and the nasal. are not in contact. A thin projection of the jugal reaches the It follows the nasal anteriorly, similar to that in some speci− orbital margin. The external nares are not completely pre− mens of Eryosuchus garjainovi or Cyclotosaurus robustus as served; therefore, the morphology of this structure is uncer− observed by Schoch (2008). On the other hand, the lacrimal tain. flexure of the infraorbital sensory canal is partially pre− FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS 559

70 mm hamate process glenoid fossa adductor tympani posterior fossa foramen dentary anterior coronoid coronoid articular middle splenial coronoid postsplenial angular surangular anterior Meckelian foramen prearticular posterior Meckelian foramen

adductor fossa

glenoid fossa hamate process mandibular sulcus

fang

surangular dentary postglenoid angular region splenial postsplenial

Fig. 5. Photographs and drawings of lower jaws of the capitosaur Calmasuchus acri gen. et sp. nov. from the Anisian at the La Mora site, Spain; specimen IPS−42407 (LM−4). Photograph (A) and drawing (B) of the hemi−mandible in lingual view. Photograph (C) and drawing (D) of the hemi−mandible in labial view. E. Postglenoid area. served, preventing observation of any Z−shaped morphol− the palatal vacuity. Although not well preserved, the presence ogy. The occipital sensory canal is absent. of an anterior process closing the vacuity on the right side of Palate.—The palate is partially preserved in IPS−37401 the palatal view allows us to reject an unpaired vacuity or a (LM−83), enabling the various palatal vacuities to be outlined medially subdivided one, as is the case in shu− (Figs. 3, 6). The vomerine plate is elongated. The trans− shkini. The ectopterygoid does not contact the interpterygoid vomerine tooth is oriented transversely. The choanal outline vacuities. The interpterygoid vacuities are equally wide along is long but its preservation prevents discrimination between their extension. narrow choanae as in Parotosuchus orenburgensis or oval− The cultriform process of the parasphenoid is preserved in shaped choanae as in Wetlugasaurus angustifrons. Neverthe− IPS−37401 (LM−83). It extends beyond the anterior border of less, the circular−subcircular outline of the choanae is re− the interpterygoid vacuities to the level of the choanae. In con− jected. Paired anterior palatal vacuities are present. trast, in the posterior region of the cultriform process, there is The palatal fragment in IPS−37401 (LM−101) (Fig. 4) no evidence of a deltoid base. The participation of the palatine shows both the major part of the vomer and the maximal out− at the margin of the interpterygoid vacuities prevents the pala− line of the choanae, although as in the case of IPS−37401 tine ramus of the pterygoid from contacting the vomer. The (LM−83) its preservation prevents discernment of the narrow pterygoid is slender. The posterior half of the palatine ramus or oval choanal morphology. Postfenestral teeth can be clearly curves medially, where it forms the corpus of the pterygoid; outlined and placed. The distance between the postfenestral then, this corpus curves laterally, forming the quadrate ramus. teeth and the posterior part of the anterior palatal vacuity is The pterygoid displays a pronounced sculpture in the palatine 5 mm. IPS−37401 (LM−101) also shows the anterior process of region and corpus. The palatine ramus and most of the corpus

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premaxilla premaxilla anterior palatal vacuity fang vomer maxilla maxilla choana infraorbital cultriform sulcus process fang 50 mm nasal palatine lacrimal supraorbital sulcus

prefrontal interpterygoid vacuity jugal temporal ectopterygoid frontal sulcus alar process of the jugal pterygoid jugal sulcus

postorbital supratemporal parasphenoid squamosal vacuity

parietal tabular quadratojugal exoccipital postfrontal postparietal supratemporal quadrate occipital condyle crista muscularis

Fig. 6. Cranial reconstruction in dorsal (A) and ventral (B) views of the capitosaur Calmasuchus acri gen. et sp. nov. from the Anisian at the La Mora site, Spain. of the pterygoid are present in IPS−37401 (LM−83), but the dorsally straight along the posterior two−thirds and slightly quadrate ramus of the pterygoid is damaged and badly pre− curved in the anterior part. In the labial view, the angular served. This region is well preserved in IPS−37401 (LM−63), shows well−defined ornamentation that becomes less evident displaying a parasagittally oriented quadrate ramus and pre− in the postsplenial. In the posterior part of the hemi−mandi− served quadrate–pterygoid suture. The suture between the ble, a weakly developed mandibular sulcus is present. The pterygoid and the parasphenoid is anteroposteriorly short. The dentary shows two anterior tusks and 47 teeth with moder− parasphenoid prevents the exoccipital from contacting the ately compressed bases. Both the dentary and the splenial pterygoid ventrally. As revealed in IPS−37401 (LM−83), the form part of the symphyseal region, as is typical in temno− parasphenoid plate, with a rectangular shape, is flattened with− spondyls. The postglenoid area is elongated and contains the out any depression or sculpturing. The crista muscularis of the articular and surangular, without any sign of the prearticular. parasphenoid is poorly preserved and can be discerned only at The angular lies ventrally to the articular. The foramen the level of the pterygoid–parasphenoid suture. The occipital chorda tympani lies in the posterior region of the glenoid condyles are located slightly anterior to the quadrate condyles. fossa, separating the articular and prearticular. Although Jupp and Warren (1986) discuss the lower jaw Occiput.—Most of the occiput is not preserved and only a anatomy of temnospondyls, the morphology of the post− few characters are available for description, because of the glenoid area cannot be clearly placed in any of the two types use of computed tomographic scans (Fig. 2). Structures of described by these authors. It shares with type I the following the occiput are recognisable only in IPS−37401 (LM−63). features: the prearticular does not extend into the postglenoid Matrix deletion and virtual repositioning of the cranial struc− area, the articular is the major component of the postglenoid tures allowed us to confirm that the quadratojugal contrib− area, the angular lies ventral to the articular, and the foramen utes to the upper jaw condyle, whereas the post−temporal chorda tympani separates the articular and prearticular. On fenestra displays a triangular morphology, as is the case of al− the other hand, as in type II, the angular lies labial to the artic− most all capitosaurs and trematosaurs. ular and the postglenoid area is elongated. Mandible.—At least seven well−preserved hemi−mandibles Moreover, the prearticular does not suture the splenial be− were recovered in the type locality. The general description cause it is separated by the coronoid. Although the mandibu− is based on IPS−42407 (LM−4) (Fig. 5), which is complete lar sutures are not clearly discernable because of taphonomic and well preserved, at a total length of 39.5 cm. The hemi− reasons, the major part of the middle coronoid probably does mandible is low except for its posterior area, which is not reach the prearticular or the posterior Meckelian fora− FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS 561 men. The posterior Meckelian foramen is short, being less than half the size of the adductor fossa (Damiani 2001) and huxleyi less than 25% of the total length of the mandible (Schoch Rhineceps nyasaensis 1 Uranocentrodon senekalensis 2000).The anterior Meckelian foramen is poorly preserved, Wetlugasaurus angustifrons but it is situated slightly in an anterior position in comparison Odenwaldia heidelbergensis 8 Vladlenosaurus alexeyevi with that in other capitosaurs. Edingerella madagascariensis The prearticular shows a well−developed, high, and mas− 6 11 Watsonisuchus spp. sive hamate process. The quadrate trochlea is shorter than the 10 Xenotosuchus africanus 2 Cherninia denwai hamate process. Comparisons of the postglenoid area with that 7 12 crookshanki of other capitosaurs allowed us to classify the mandible of 13 Stanocephalosaurus pronus 14 Calmasuchus acri as type IV of Maryańska and Shishkin 16 Stanocephalosaurus birdi 9 15 Procyclotosaurus stantonensis Eocyclotosaurus spp (1996), with an elongated postglenoid area and a depressed 17 dorsal surface. The crista articularis is poorly preserved but is 18 Quasicyclotosaurus campi Parotosuchus orenburgensis displaced and continuous with the crista medialis. The glenoid Calmasuchus acri fossa lies above the dorsal surface of the dentary. The adductor 19 Cyclotosaurus robustus 20 22 Tatrasuchus wildi fossa is short. As in most capitosaurs, the labial wall of the 21 Eryosuchus garjainovi adductor fossa is straight and horizontal. 23 Mastodonsaurus giganteus Benthosuchus sushkini 3 yakovlevi 4 Angusaurus spp Phylogenetic analysis 5 brauni Lydekkerina huxleyi Rhineceps nyasaensis In order to investigate the phylogenetic relationships of the Uranocentrodon senekalensis Wetlugasaurus angustifrons new taxon, we incorporated its characters into a data matrix. Odenwaldia heidelbergensis We also scored Vladlenosaurus alexeyevi in a cladistic anal− Vladlenosaurus alexeyevi Edingerella madagascariensis ysis, for the first time. This form was recovered from the late Watsonisuchus spp Vetlugian of Russia and confined to lacustrine habitats, and it Xenotosuchus africanus shows an outline very similar to benthosuchids (Bystrow Cherninia denwai Paracyclotosaurus crookshanki 1940; Getmanov 1989; Novikov 1990), although some cra− Stanocephalosaurus pronus nial characters are similar to Wetlugasaurus (Morkovin and Stanocephalosaurus birdi Procyclotosaurus stantonensis Novikov 2000; Shishkin et al. 2006). The data matrix was an Eocyclotosaurus spp. updated version of Damiani (2001), with new characters and Quasicyclotosaurus campi different coded taxa. Recent capitosaur findings (Morales Parotosuchus orenburgensis Calmasuchus acri and Shishkin 2002; Steyer 2003; Damiani 2008; Schoch Cyclotosaurus robustus 2008; Maganuco et al. 2009) provided new information on Tatrasuchus wildi Eryosuchus garjainovi the cranial characters of the group; therefore, an upgrade of Mastodonsaurus giganteus the Damiani (2001) matrix was required. From the original Benthosuchus sushkini Thoosuchus yakovlevi matrix, two characters were deleted because they were unin− Trematosaurus brauni formative (characters 22 and 34; see Damiani 2001 for char− Angusaurus spp. acter details). In addition, eight characters were added to the matrix (see Appendix 1). These characters were previously Fig. 7. Cladogram of the capitosaurs analysed in the data matrix. A. One of used in cladistic analysis and provided informative data the two most parsimonious trees. B. Consensus trees (strict and majority (Schoch 2000, 2008; Maganuco et al. 2009). rule show identical topology) of the two most parsimonious trees. The analysis was performed by using PAUP 4.0 beta 1.0 for PC (Swofford 2001). The data matrix consisted of 53 char− series in which the otic notch is gradually closed posteriorly, acters and 26 terminal taxa, with three terminal taxa as an as indicated by Damiani (2001). Delayed transformation outgroup taxon (Rhineceps nyasaensis, Uranocentrodon (DELTRAN) and Accelerated transformation (ACCTRAN) senekalensis,andLydekkerina huxleyi).Thetaxaanalysed were selected to optimize the character transformation. Taxa (see Appendix 2) are considered at the species level, except for coded as having multiple states were treated as polymorphic. Angusaurus, Eocyclotosaurus,andWatsonisuchus;forthese We used a heuristic search with simple addition sequence and taxa, we preferred to use the characters of the genus rather than only one tree at each step during stepwise addition and 10,000 those of the species, as exemplified by Damiani (2001), replicates. Tree−Bisection−Reconnection branch swapping was Damiani and Yates (2003), or Maganuco et al. (2009). Char− performed and zero−length branches were collapsed to yield acters were scored by using information from the literature polytomies. See Appendix 3 for further details. and JF personal observations (see Appendix 2). All charac− Our phylogenetic analysis resulted in two most parsimo− ters were equally weighted and left unordered, except charac− nious trees of 141 steps each (CI = 0.41, RI = 0.70, RC = ter 4 (tabular horn), because it forms a clear transformational 0.29). As reported by Damiani (2001) and Maganuco et al.

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(2009), a high amount of homoplasy was suspected in the 1970) but unlike those of stenotosaurids, where the inter− evolution of the group, resulting in a low CI value. The strict pterygoid vacuities are tapered posteriorly. In addition, the and majority−rule consensus trees of the two most parsimoni− otic notch and tabular horns appear to be more primitive in ous trees were identical (Fig. 7) and showed one unresolved Calmasuchus than in stenotosaurids and related forms, polytomy at the level of the clade composed of Cycloto− where the squamosal usually contacts the tabular to create an saurus robustus, Tatrasuchus wildi, Mastodonsaurus gigan− embayment that is not found in Calmasuchus. teus, and Eryosuchus garjainovi. Regarding the affinities of the material described here with The support for the single nodes and their robustness ac− Eryosuchus, as suggested by Damiani (2001), we compared cording to bootstrap were low. Only seven nodes reached Calmasuchus acri with the eryosuchids sensu Schoch and bootstrap values higher than 50% (1, 100%; 2, 93%; 4, 71%; Milner (2000) from the Eastern European platform. In the case 5, 94%; 9, 69%; 16, 77%; 18, 94%). In brief, this indicated of the capitosaur described here, the tip of the tabular is rela− that, apart from the Capitosauria and Trematosauria, only the tively wide throughout its length, with a slight anterodistally trematosaurs and few capitosaur clades are well supported. expansion. This morphology differs from Eryosuchus gar− The clade notation used in the paper (taxon X + taxon Y) re− jainovi, because the anterodistal expansion is well developed fers to the least inclusive clade in the resolved cladogram com− in the latter taxon. In Calmasuchus, the orbital size is reduced prising the two given taxa and does not imply that these taxa compared with that of Eryosuchus and resembles the me− share a direct sister−taxon relationship. Node numbers are in− dium−sized orbits of Parotosuchus or Tatrasuchus wildi.The dicated in Fig. 7. The phylogenetic discussion is based on outline of the orbits in Eryosuchus garjainovi is slightly more most parsimonious tree number 1, whose topology is congru− elongated and suboval than in Calmasuchus acri. The propor− ent to that of the consensus trees. See Appendix 4 for the tional interorbital distance is smaller in Calmasuchus acri than apomorphy list and more details about the character evolution. in Eryosuchus garjainovi; the position of the orbits in the skull roof in both genera is similar. Damiani (2001) used the posi− tion of the occipital condyles in relation to the quadrate con− Discussion dyles as one of the characters to group the Russian Eryosuchus species with the Gondwanian ones: in Eryosuchus, the occipi− Previous morphological studies.—Previous studies on some tal condyles are slightly anterior to the quadrate condyles. This of the already described material suggest close affinities to is also the case in Calmasuchus acri, whereas some Gondwa− Parotosuchus sp. (Gaete et al. 1993, 1994, 1996). These au− nian species such as Stanocephalosaurus pronus and Xenoto− thors published a preliminary reconstruction of the material suchus africanus differ, with the occipital condyles at the same and referred it to the genus Parotosuchus, reporting the pres− level (or posterior) as the quadrate condyles. ence of paired anterior palatal vacuities as a rather distinctive In the lower jaw, the postglenoid form of Calmasuchus morphology from this genus. However, this is not the only dif− acri is well extended and slightly concave without a medial ference between Parotosuchus sp. and Calmasuchus acri:the ridge aligned sagitally as it is possible to observe in Eryo− tabular morphology differs, being posteriorly directed in all suchus. On the other hand, the morphology of the posterior the specimens of Parotosuchus and posterolaterally directed Meckelian foramen is short, differing from the elongated in those of Calmasuchus acri. The relative orbital size of morphology found in Eryosuchus species. Parotosuchus sp. and Calmasuchus acri is similar, but they differ in their orbital margins, which are elevated in Paroto− Comparisons with other taxa.—Posterolaterally directed suchus specimens and flushed in the same plane in Calma− tabular horns are considered by Schoch and Milner (2000) suchus acri. Differences are also present in the mandibles, es− and Damiani (2001) as a derived character for the following pecially in the postglenoid area. Parotosuchus orenburgensis capitosaurs: Cherninia denwai, Eryosuchus, Xenotosuchus resembles type III of Maryańska and Shishkin (1996) whereas africanus, Mastodonsaurus giganteus, Stanocephalosaurus Calmasuchus acri belongs to type IV. pronus, Paracyclotosaurus crookshanki, and Tatrasuchus More recently, some authors, based on the descriptions wildi. The tabular horns in Calmasuchus acri are slightly and drawings supplied from the first papers, suggested that anterodistally broadened, and this expansion is more distinct the La Mora specimens could be referred to as a stenoto− in Eryosuchus. Further, Calmasuchus acri lacks a long pro− saurid indet. (Shishkin 2000) or Eryosuchus sp. (Damiani cessus lateralis in the tabular horns (present in Tatrasuchus 2001). However, the material described here cannot be at− wildi and Stanocephalosaurus pronus). Altogether, these are tributed to stenotosaurids because it does not display the indications of a more derived condition in the horn morphol− prefrontal–postorbital contact, typical of stenotosaurids (and ogy of Eryosuchus, Tatrasuchus, and Stanocephalosaurus heylerosaurids). Its supraorbital sensory canal is slightly dis− pronus than of Calmasuchus. placed laterally in Calmasuchus acri and contacts the lacri− The orbital size, in proportion to the skull, is smaller than mal–nasal suture, as in some specimens of Cyclotosaurus that of Mastodonsaurus giganteus and similar to those of robustus and other capitosaurs such as Eryosuchus gar− Parotosuchus orenburgensis and Tatrasuchus kulczyckii.The jainovi; its interpterygoid vacuities are equally wide along relative position between the postorbital and the prefrontal their extension, as in Stanocephalosaurus pronus (Howie varies in capitosaurs. This character is also considered derived FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS 563 when these bones are near each other by thin projections the case of Xenotosuchus africanus, which displays a short (Schoch 2008). This is the case of Calmasuchus acri and dif− posterior Meckelian foramen. fers from other advanced capitosaurs, where the bones are The length of the adductor fossa is short in Calmasuchus widely separated, such as in Eryosuchus, Tatrasuchus,or acri and, when compared with the total length of the mandi− Xenotosuchus, and resemble the condition found in Para− ble, similar to that of Mastodonsaurus giganteus and Eryo− cyclotosaurus and Stanocephalosaurus. suchus garjainovi. On the other hand, the outline morphol− In the palatal view, the region between the anterior palatal ogy of Calmasuchus acri resembles the Tatrasuchinae. This vacuity and the anterior border of the interpterygoid vacu− group combines parotosuchid−like features with other fea− ities (occupied by the two vomerine plates) is elongated as in tures usually found in cyclotosaurs (Schoch and Milner Parotosuchus orenburgensis and Stanocephalosaurus pro− 2000). Calmasuchus acri differs from the tatrasuchinids in nus, and considered a derived character (Damiani 2001; several characters, as already discussed: less separated post− Schoch 2008). The same authors considered oval or narrow orbital and prefrontal, supraorbital sensory canal traversing slit−like choanae as plesiomorphic (e.g., Calmasuchus acri or the nasal and lacrimal, more elongated prefenestral division Benthosuchus sushkini) and subcircular or circular choanae of the palate, narrower choanae, divided anterior palatal va− as apomorphic (Liu and Wang 2005; e.g., Yuanansuchus cuity (it is undivided in the two species of Tatrasuchus), laticeps or Mastodonsaurus giganteus). In Tatrasuchus wildi, equally wide interpterygoid vacuities anteriorly and posteri− the snout is very short and broad with foreshortened vome− orly (they are tapered posteriorly in Tatrasuchus wildi and rine plates and subcircular choanae. Calmasuchus acri lacks unpreserved in T. kulczyckii), no sculptured ventral surface a ventral exoccipital–pterygoid contact, a character also of the parasphenoid basal plate, shorter posterior Meckelian present in Tatrasuchus wildi and Xenotosuchus africanus, foramen, and postglenoid area longer than the glenoid facet. differing from Eryosuchus garjainovi and Tatrasuchus wildi. The inclusion of Calmasuchus acri in any of the capito− Although the presence of unpaired or paired anterior pal− saur families recognised in the literature (see Schoch and atal vacuities is often considered a diagnostic character in Milner 2000 for further details) is controversial because the trematosaurs (Welles and Cosgriff 1965; Damiani 2001), this combination of characters present in this new genus is not character is also phylogenetically informative in capitosaurs. in agreement with the synapomorphies used to define the Calmasuchus acri has a paired anterior palatal vacuity, as different families (sensu stricto Schoch and Milner 2000). does Mastodonsaurus giganteus. In most specimens of Eryo− Therefore, a re−definition of some capitosaur families (i.e., suchus, this character represents the primitive condition, but Parotosuchidae, Tatrasuchidae, Eryosuchidae) will be neces− it was referred by Schoch and Milner (2000) from a gigantic sary. Nevertheless, as some aspects of Calmasuchus acri re− undescribed specimen. main undiscovered, we prefer to be conservative, discarding Pronounced sculpturing in the palatine region of the ptery− its inclusion in any capitosaur family or even creating a new goid is present mainly in trematosaurs, but this character is one, until additional material allows accurate assessment of variable in capitosaurs. Basal and “advanced” forms such as the characters that remain unclear. Wetlugasaurus angustifrons, Tatrasuchus wildi, Cyclotosau− rus robustus, Eocyclotosaurus lehmani, and the capitosaur de− scribed herein show ornamentation, whereas other forms such Phylogenetic remarks as Cherninia denwai, Eryosuchus garjainovi, Mastodonsau− rus giganteus, Paracyclotosaurus crookshanki,andStano− The dichotomy between the Trematosauria and the Capito− cephalosaurus pronus display the ventrally smoothed palatine sauria was recognised in previous studies (Yates and Warren without any sign of ornamentation. 2000; Damiani 2001; Steyer 2002; Damiani and Yates 2003; Maryańska and Shishkin (1996) recognised four patterns Schoch et al. 2007; Schoch 2008; Maganuco et al. 2009). in the postglenoid area of capitosaurs. They referred to the Herein, the capitosaur clade is also recognised and well sup− plesiomorphic condition in Wetlugasaurus angustifrons.The ported by seven unambiguous synapomorphies. postglenoid area of eryosuchids, mastodonsaurids, and tatra− Benthosuchus sushkini was previously included in the suchinids was considered as the most derived one, with the capitosaur clade (Yates and Warren 2000; Damiani 2001; retroarticular process markedly elongated and depressed in the Steyer 2003). However, Damiani and Yates (2003) indicated dorsal surface (Maryańska and Shishkin 1996). This morphol− that three characters (the lacrimal flexure of the infraorbital ogy is also recognised in Calmasuchus acri, being more de− sensory canal, morphology of the marginal teeth, and oblique rived than the morphology present in Xenotosuchus africanus. ridge of the pterygoid) were incorrectly coded in the revision The morphology of the posterior Meckelian foramen in by Damiani (2001). This problem is resolved here and con− Calmasuchus acri represents the primitive condition (Schoch firms the basal position of Benthosuchus sushkini in the 2000; Damiani 2001), differing from the derived condition trematosaurian clade. found in Eryosuchus garjainovi and Mastodonsaurus gigan− The Trematosauroidea (node 4) were defined as the last teus. Moreover, the type mandible of Tatrasuchus kulczyckii is common ancestor of Thoosuchus yakovlevi and Tremato− incomplete, but it is inferred that its posterior Meckelian fora− saurus brauni and all its descendants (Yates and Warren men is elongated (Maryańska and Shishkin 1996). This is not 2000). This was confirmed by Damiani and Yates (2003),

http://dx.doi.org/10.4202/app.2010.0025 564 ACTA PALAEONTOLOGICA POLONICA 56 (3), 2011

Maganuco et al. (2009), and the present study. Tremato− (2001), retaining W. gunganj, W. magnus, W. rewanensis,and saurus brauni is included in the trematosaurian clade as the W. aliciae with caution in the genus Watsonisuchus.More− sister taxon of Angusaurus, yet considered a more primitive over, the analysis reflects the close, sister−taxon relationships form (Damiani and Yates 2003). between Edingerella and Watsonisuchus. The more recent update of the Capitosauria (node 6) Xenotosuchus africanus, Cherninia denwai, and Para− (Damiani and Yates 2003) defined the group as stereopondyls cyclotosaurus crookshanki form successive sister taxa to the that share a more recent common ancestor with Parotosuchus remaining stenotosaurids and heylerosaurids plus Stanoce− than with Trematosaurus. Wetlugasaurus was included in the phalosaurus. Regarding Stanocephalosaurus, we consider S. trematosaurian group (Schoch 2000; Schoch and Milner birdi as the senior synonym of P. peabodyi and separated it 2000), although other authors consider it as a basal capitosaur from Wellesaurus. On the other hand, the South African or sister group to them (Ochev 1966; Kamphausen 1989; capitosaur S. pronus was included as an Eryosuchus member Maryańska and Shishkin 1996; Damiani 2001; Damiani and (Damiani 2001). This suggestion was not followed here. In Yates 2003). A recent analysis (Schoch 2008; Maganuco et al. the present analysis, S. birdi and S. pronus are sister taxa, 2009) indicated Wetlugasaurus as a member of the Capito− with two unambiguous synapomorphies, demonstrating that sauria. In the present study, Wetlugasaurus appears as the most this genus had widespread distribution, being present in basal member of the Capitosauria. Therefore, we define the and North America. Capitosauria as stereopondyls that share a more recent com− The close relationship between the poorly known steno− mon ancestor with Wetlugasaurus than with Trematosaurus. tosaurids (Paton 1974; e.g., Procyclotosaurus stantonensis) The position of Vladlenosaurus alexeyevi within the and heylerosaurids (e.g., Eocyclotosaurus and Quasicycloto− Capitosauria is controversial. This taxon was suggested to be a saurus) was indicated by Schoch and Milner (2000). Here, species of Wetlugasaurus (Shishkin et al. 2006) or closely re− stenotosaurids appear as a sister taxon of heylerosaurids, the lated to this genus (Morkovin and Novikov 2000). In the pres− latter forms being more advanced. On the other hand, the ent analysis, Vladlenosaurus alexeyevi and the enigmatic present analysis seems to partially corroborate the hypothesis Odenwaldia heidelbergensis resulted as sister taxa. of the diphyli between Eocyclotosaurus and Cyclotosaurus On the other hand, the Watsonisuchus–Edingerella clade (Damiani 2001), which are not closely related forms. Other− appears as the sister group of the huge clade of Gondwanian wise, the Eocyclotosaurus–Odenwaldia relationship is not forms, plus heylerosaurids and stenotosaurids, being the more supported here. primitive forms of the clade. The position of Edingerella The cosmopolitan genus Parotosuchus is known to be madagascariensis is controversial. It was initially described as from the . Recent published papers clarified the a species of Benthosuchus (Lehman 1961) and later to the ge− valid species of this genus (e.g., Schoch and Milner 2000; nus Parotosuchus, and then assigned to the capitosaur group Damiani 2001; Morales and Shishkin 2002; Shishkin and (Schoch 2000) and surprisingly to the lydekkerinid group Sulej 2009 and references therein). To date, at least eight spe− (Damiani 2001). Finally, the genus Edingerella was estab− cies are considered valid: Parotosuchus orenburgensis, P. lished for the species E. madagascariensis (Schoch and nasutus, P.helgolandicus, P. orientalis, P. komiensis, P. bog− Milner 2000), defined as a stem capitosaur. Recently, a new doanus, P. panteleevi, and P. speleus. In the present analysis, description of Lehman's (1961) specimens and new excep− P. orenburgensis is the sister taxon of Calmasuchus acri and tionally well−preserved specimens (Steyer 2003; Maganuco et their descendants, supported by two unambiguous synapo− al. 2009) indicated the basal position of this genus within the morphies. The new capitosaur described here, Calmasuchus capitosaur group and its close relationship with Watsoni− acri, appears as a more derived form than Parotosuchus suchus, although in a recent revision of the group, Schoch orenburgensis and the sister taxon of the Cyclotosaurus– (2008) included Edingerella madagascariensis within the Tatrasuchus and Eryosuchus–Mastodonsaurus clades, re− trematosaurs. In the case of Watsonisuchus, these taxa are vealing a more basal position than the tatrasuchines. studied here at the genus level. Four species (Watsonisuchus Finally, we report a dichotomy between cyclotosaurs and aliciae, W. gunganj, W. magnus,andW. rewanensis)have related forms (e.g., Tatrasuchus)andtheEryosuchus–Masto− been described from the Early Triassic of Australia and South donsaurus clade. On one hand, Cyclotosaurus robustus and Africa; they are considered as one of the most basal genera Tatrasuchus wildi were found to be sister taxa in previous within the Capitosauria (Damiani 2001). However, W. gunjanj works (Maryańska and Shishkin 1996; Schoch and Milner and W. aliciae were transferred to the genus Rewanobatrachus 2000; Damiani 2001; Maganuco et al. 2009; present study). (Schoch and Milner 2000), another stem−capitosaur. Watsoni− On the other hand, the cladistic analysis indicated phylogen− suchus aliciae remains the best known species documented by etic affinities between mastodonsaurids and eryosuchids as ontogenetical information (Warren 1980; Warren and Schroe− previously reported by other authors (Maganuco et al. 2009). der 1995). Damiani (2001) retained W. aliciae within the ge− Further research is needed on related taxa, such as the Anisian nus with caution. Recently, the genus Warrenisuchus (Mag− Heptasaurus, Komatosuchus, and the gigantic undescribed anuco et al. 2009) was established for W. aliciae (Warren and skull from of Russia referred by Schoch and Milner Hutchinson 1988). This genus is considered basal to (2000) to Eryosuchus sp., to clarify the relationships within Watsonisuchus. In the present study, we followed Damiani this clade. FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS 565

(ed.), Excursiones del III Coloquio Estratigráfico y Paleogeográfico del Conclusions Pérmico y Triásico de España, 1–53. Cuenca. Calzada, S. 1987. Niveles fosiliferos de la facies Buntsandstein (Trias) en el The capitosaur remains recovered from the La Mora site sector norte de los Catalanides. Cuadernos de Geología Ibérica 11: (Eastern Iberian Peninsula) allowed us to describe a new 256–271. Cosgriff, J.W. and Defaw, S.L. 1987. A capitosaurid labyrinthodont from form of capitosaur, Calmasuchus acri. The remains date to the Lower Scythian of Tasmania. Alcheringa 11: 21–41. the early−to−middle Anisian (Middle Triassic). Its cranial re− Damiani, R.J. 2001. A systematic revision and phylogenetic analysis of construction suggests that this capitosaur does not belong to Triasic mastodonsauroids (Temnospondyli: Stereospondyli). Zoologi− Parotosuchus, Eryosuchus, or a stenotosaurid indet., as pre− cal Journal of the Linnean Society 133: 379–482. viously suggested (Gaete et al. 1993, 1994, 1996; Shishkin Damiani, R.J. 2004. Temnospondyls from the (Karoo Ba− 2000; Damiani 2001). The new capitosaur is characterised sin) of South Africa and their biostratigraphy. Gondwana Research 7: 165–173. by a combination of parotosuchid characters and others such Damiani, R.J. 2008. A giant skull of the temnospondyl Xenotosuchus as posterolaterally directed tabular horns, paired anterior pal− africanus from the Middle Triassic of South Africa and its ontogenetic atal vacuities, and unique morphological characters in its implications. Acta Palaeontologica Polonica 53: 75–84. lower jaw. The outline of the skull resembles that of tatra− Damiani, R.J. and Yates, A.M. 2003. The Triassic Thoosuchus suchines, but several different character polarities demon− yakovlevi and the relationships of the Trematosauroidea (Temnospon− strate the basal position of the new form ahead of the tatra− dyli: Stereospondyli). Records of the Australian Museum 55: 331–342. Dinarès−Turell, J., Diez, B.J., Rey, D., and Arnal, I. 2005. “Buntsandstein” suchines. The phylogenetic analysis suggests that Paroto− magnetostratigraphy and biostratigraphic reappraisal from eastern Iberia: suchus orenburgensis and Calmasuchus acri are the sister Early and Middle Triassic stage boundary definitions through correlation taxa of the Cyclotosaurus–Tatrasuchus and Eryosuchus– to Tethyan sections. Palaeogeography, Palaeoclimatology, Palaeoeco− Mastodonsaurus clades. Calmasuchus acri is more derived logy 229: 158–177. than Parotosuchus sp. As a group, the Capitosauria are sup− Gaete, R., Galobart, A., and Ros, X. 1993. 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The Madagascarian Edingerella is sistemáticos y bioestratigráficos del yacimiento de tetrápodos fósiles de la the sister taxon of Watsonisuchus. facies Buntsandstein de La Mora (Pla de la Calma, Barcelona). Cuadernos de Geologia Iberica 20: 331–345. Getmanov, S.N. 1989. Triassic amphibians of the East European platform (Family Benthosuchidae Efremov) [in Russian]. Trudy Paleontologi− Acknowledgements českogo Instituta Akademii Nauk SSSR 236: 1–102. Hancox, P.J., Shishkin, M.A., Rubidge, B.S., and Kitching, J.W. 1995. A We thank Igor Novikov and Mikhail Shishkin (PIN, Moscow, Russia) threefoldsubdivision of the Assemblage Zone (Beaufort for their hospitality and useful discussions during the visit to the Rus− Group, SouthAfrica) and its paleogeographical implications. South Af− sian collections; Jean−Sébastien Steyer (MNHN, Paris, France) for rican Journal of Science 91: 143–144. reading the early version of the manuscript and helpful comments; Howie, A.A. 1970. 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Benthosuchus shushkini Efr.—A laby− Palaegeography, Palaeclimatology, Palaeoecology 143: 347–384. rinthodont from the Eotriassic of Sharjenga river [in Russian]. Trudy Maganuco, S., Steyer, J.S., Pasini, G., Boulay, M., Lorrain, S., Bénéteau, Paleontogičeskogo Instituta Akademii Nauk SSSR 10: 1–152. A., and Auditore, M. 2009. An exquisite specimen of Edingerella Calvet, F. and Marzo, M. 1994. El Triasico de las Cordilleras Costero madagascarensis (Temnospondyli) from the Lower Triassic of NW Catalanas: estratigrafia, sedimentologia y analisis secuencial. In:A.Arche Madagascar; cranial anatomy, phylogeny, and restorations. Memorie

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della Società Italiana di Scienze Naturali e del Museo Civico di Storia continental Triassic on the basis of tetrapods. Memoires de Géologie 22: Naturale di Milano 36: 1–72. 121–125. Márquez−Aliaga, A., Valenzuela−Ríos, J.I., Calvet, F., and Budurov, K. 2000. Shishkin, M.A. and Sulej, T. 2009. The Early Triassic temnospondyls of the Middle Triassic conodonts from northeastern Spain: biostratigraphic im− Czatkowice 1 tetrapod assemblage. Palaeontologia Polonica 65: 31–77. plications. Terra Nova 12: 77–83. Shishkin, M.A., Rubidge, B.S., and Hancox, P.J. 1995. Vertebrate biozonation Maryańska, T. and Shishkin, M.A. 1996. New cyclotosaurid (Amphibia: of the Upper Beaufort Series of South Africa—a new look on correlation Temnospondyli) from the Middle Triassic of Poland and some prob− of the Triassic biotic events in Euramerica and southern Gondwana. In:A. lems of interrelationships of capitosauroids. Prace Muzeum Ziemi 43: Sun and Y. Wang (eds.), Sixth Symposium on Mesozoix Terrestrial Eco− 54–83. systems and Biota, Short Papers, 39–41. China Ocean Press, Beijing. Morales, M. and Shishkin, M.A. 2002. A re−assessment of Parotosuchus Shishkin, M.A., Sennikov, A.G., Novikov, I.V., and Ilyina, N. 2006. Differ− africanus (Broom), a capitosauroid temnospondyl amphibian from the entiation of tetrapod communities and some aspects of biotic events in Triassic of South Africa. Journal of Vertebrate Paleontology 22: 1–11. the Early Triassic of Eastern Europe. Paleontological Journal 40: 1–10. Morkovin, I.V. and Novikov, I.V. 2000. A new Labyrinthodont from the Solé de Porta, N., Calvet, F., and Torrentó, L. 1987. Analisis palinologico Lower Triassic of the Luza River Basin (Komi Republic) [in Russian]. del Triásico de los catalanides (NE España). Cuadernos de Geologia Izvestiâ Vysših Učebnyh Zavedenii, Geologiâ i Razvedka 3: 29–35. Ibérica 11: 237–254. Novikov, I.V. 1990. New early Triassic labyrinthodonts from Central Timan Steyer, J.S. 2002. The first articulated trematosaur “amphibian” from the [in Russian]. Paleontologičeskij žurnal 1990: 87–100. Lower Triassic of Madagascar: implications for the phylogeny of the Ochev, V.G. [Očev, V.G.] 1966. Sistematika ifilogeniâ kapitozavroidnyh group. Palaeontology 45: 771–793. labirintodontov. 184 pp. Izdatel'stvo Saratovskogo Universiteta, Saratov. Steyer, J.S. 2003. A revision of the Early Triassic “Capitosaurs” (Stego− cephali, Stereospondyli) from Madagascar, with remarks on their com− Ochev, V.G. and Shishkin, M.A. 1989. On the principles of global correla− parative ontogeny. Journal of Vertebrate Paleontology 23: 544–555. tion of the continental Triassic on the tetrapods. Acta Palaentologica Sulej, T. and Majer, D. 2005. The temnospondyl amphibian Cyclotosaurus Polonica 34: 149–173. from the Upper Triassic of Poland. Palaeontology 48: 157–170. Paton, R.L. 1974. Capitosauroid labyrinthodonts from the Trias of England. Swofford, D.L. 2001. PAUP: Phylogenetic Analysis Using Parsimony, Ver− Palaeontology 17: 253–290. sion 4.0b10. Smithsonian Institution, Washington DC. Schoch, R.R. 1997. A new capitosaur amphibian from the Upper Lettenkeuper Warren, A.A. 1980. Parotosuchus from the Early Triassic of Queensland (Triassic: Ladinian) of Kupferzell (South Germany). Neues Jahrbuch für and Western Australia. Alcheringa 15: 43–64. Geologie und Paläontologie, Abhandlungen 203: 239–272. Warren, A.A. and Hutchinson, M.N. 1988. The Madagascan Capitosaurs. Schoch, R.R. 1999. Comparative osteology of Mastodonsaurus giganteus Bulletin du Muséum National d’Histoire Naturelle Paris 10C: 23–30. (Jaeger, 1828) from the Middle Triassic (Lettenkeuper: Longobardian) Warren, A.A. and Schroeder, N.1995. Changes in the capitosaur skull with of Germany (Baden−Württemberg, Bayern, Thüringen). Stuttgarter growth: an extension of the growth series of Parotosuchus aliciae Beiträge zur Naturkunde Serie B 278: 1–175. (Amphibia, Temnospondyli) with comments on the otic area of capito− Schoch, R.R. 2000. The origin and intrarelationships of Triassic capito− saurs. Alcheringa 19: 41–46. saurid amphibians. Palaeontology 43: 705–727. Watson, D.M.S. 1962. The evolution of the labyrinthodonts. Philosophical Schoch, R.R. 2008. The capitosauria (Amphibia): characters, phylogeny, Transactions of the Royal Society of London, Series B 245: 219–265. and stratigraphy. Palaeodiversity 1: 189–226. Welles, S.P. and Cosgriff, J. 1965. A revision of the labyrinthodont family Schoch, R.R. and Milner, A.R. 2000. Stereospondyli. In: P. Wellnhofer (ed.), capitosauridae and a description of Parotosaurus peabody,n.sp.fromthe Encyclopedia of Paleoherpetology 3B. 203 pp. Verlag Dr. Friedrich Pfiel, Wupatki member of the Moenkopi Formation of Northern Arizona. Uni− München. versity of California Publications in Geological Sciences 54: 1–148. Schoch, R.R., Fastnacht, M., Fichter, J., and Keller, T. 2007. Anatomy and re− Witzmann, F. and Gassner, T. 2008. Metoposaurid and mastodonsaurid lationships of the Triassic temnospondyl Sclerothorax. Acta Palaeonto− stereospondyls from the Triassic– boundary of Portugal. Alche− logica Polonica 52: 117–136. ringa 32: 37–51. Shishkin, M.A. 2000. Olenekian–Anisian boundary in the history of land Yates, A.M. and Warren, A.A. 2000. The phylogeny of the “higher” tetrapods. In: E. Gradinaru (ed.), Workshop on the Lower–Middle Trias− temnospondyls (Vertebrata: Choanata) and its implications for the sic (Olenekian–Anisian) Boundary, 60–69. Tulcea. monophyly and origins of the Stereospondyli. Zoological Journal of the Shishkin, M.A. and Ochev, V.G. 1994. Problems of global correlation of the Linnean Society 128: 77–121. FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS I Appendix 1: Character data The character data were composed of 53 characters. Of these, 45 cor− 48. The interpterygoid vacuities are as wide posteriorly as anteri− respond to the 47 characters used in the data matrix of Damiani orly (0), or the basipterygoid ramus of the pterygoid is medially (2001). We excluded characters 22 (posterolateral process of the thickened and constricts the interpterygoid vacuities (1). vomer) and 34 (cheek region of the skull) of Damiani (2001) because 49. The basal plate of the parasphenoid is quadrangular in outline these characters were uninformative in the present analysis. We (0), or it is extends posterolaterally to give a trapezoidal outline maintained the order of the remaining characters and added eight ad− (1). ditional ones at the end of the list. We therefore referred to Damiani 50. The posterior margin of the squamosal is straight or curved in a (2001) for a detailed description of characters 1–45. The additional slightly convex manner (0), or it forms a posteriorly extended characters are from other phylogenetic studies: characters 46–51 plate that roofs the occiput (1). from Schoch (2000), character 52 from Maganuco et al. (2009), and 51. The postglenoid area forms a short, rounded outgrowth with character 53 from Schoch (2008). They are described as follows: oblique dorsal and ventral margins (0), or it is much elongated 46. The parietal longer than the supratemporal and much longer and has a straight dorsal margin bilaterally (1). than the postparietal (0); the parietal abbreviated, so that it, the 52. The skull greatest width−to−midline length in adults is 0.8–1.2 postparietal, and the supratemporal are of similar length (1). (0), <0.8 (1), >1.2 (2) cm. 47. The postparietal and tabular are shorter than the parietal and 53. The postorbital and prefrontal are widely separated (0), near supratemporal (0), or they extend posteriorly to give bones of each other with thin projections (1), or sutured, excluding the similar length (1). jugal from the orbital margin (2). Appendix 2: Analysed taxa The data includes the source literature (cited parenthetically) and 9. Mastodonsaurus giganteus Jaeger, 1828 (Schoch 1999) actual specimens studied by one author (JF) 10. Odenwaldia heilderbergensis Morales and Kamphausen, 1984 Outgroup (Morales and Kamphausen 1984; Schoch 2008) 1. Lydekkerina huxleyi Lydekker, 1889 (Jeannot et al. 2006) 11. Paracyclotosaurus crookshanki Mukherjee and Sengupta, 1998 2. Rhineceps nyasaensis Haughton, 1927 (Watson 1962; Schoch (Mukherjee and Sengupta 1998; Damiani 2001) and Milner 2000; Damiani 2001) 12. Parotosuchus orenburgensis Konzhukova, 1965 (Welles and 3. Uranocentrodon senekalensis Van Hoepen, 1917 (Schoch and Crosgriff 1965; Schoch and Milner 2000; Damiani 2001). Spec− Milner 2000; Damiani 2001; Latimer et al. 2002) imens: PIN 951/42 Procyclotosaurus stantonensis Ingroup 13. Woodward, 1904 (Paton 1974; Damiani 2001) 1. Angusaurus spp. Getmanov, 1989 (Getmanov 1989; Novikov 14. Quasicyclotosaurus campi Schoch, 2000 (Schoch and Milner 1990). Specimens: A. dentatus (PIN 4196/1), A. tsylmensis (PIN 2001; Liu and Wang 2005; Schoch 2008) 4333/6) 2. Benthosuchus sushkini Efremov, 1929 (Bystrow and Efremov 15. Stanocephalosaurus birdi Brown, 1933 (Welles and Cosgriff 1940). Specimens: PIN 2424/4, PIN 19−2252, PIN 41−2252, PIN 1965; Damiani 2001) 42−2252, PIN 48−2252, PIN 2424/10 16. Stanocephalosaurus pronus Howie, 1970 (Howie 1970) 3. Calmasuchus acri Fortuny, Galobart, and de Santisteban, present 17. Tatrasuchus wildi Schoch, 1997 (Schoch 1997; Damiani 2001) study (Gaete et al. 1993, 1994, 1996, present study). Specimens: 18. Trematosaurus brauni Burmeister 1849 (Schoch and Milner IPS−37401 (LM−83, LM−63, LM−101, L and M1) 2000). Specimens: MB−Am−593, MB−Am−959, MB−Am−961, 4. Cherninia denwai Mukherjee and Sengupta, 1998 (Mukherjee MB−Am−964, MB−Am−965 and Sengupta 1998; Damiani 2001) 19. Thoosuchus yakovlevi Riabinin, 1927 (Damiani and Yates 2003) 5. Cyclotosaurus robustus Meyer and Plieninger, 1844 (Schoch and 20. Vladlenosaurus alexeyevi Morkovin and Novikov, 2000 (Mor− Milner 2000; Schoch 2008) kovin and Novikov 2000) 6. Edingerella madagascarensis Lehman, 1961 (Lehman 1961; 21. Watsonisuchus spp. Ochev 1966 (Warren 1980; Warren and Warren and Hutchinson 1988; Steyer 2003; Maganuco et al. Schroeder 1995; Damiani 2001; Maganuco et al. 2009) 2009). Specimens: MNHN MAE 3002, MAE 3003, MAE 3009 22. Wetlugasaurus angustifrons Riabinin, 1930 (Bystrow and Efre− 7. Eocyclotosaurus spp. Ortlam, 1970 (Kamphausen and Morales mov 1940; Welles and Crosgriff 1965; Shishkin et al. 2000). 1981; Kamphausen 1989; Schoch 2000) Specimens: PIN 4418/1, PIN 524, PIN 3818/1, PIN 3851/115 8. Eryosuchus garjainovi Ochev, 1966 (Ochev 1966). Specimens: 23. Xenotosuchus africanus Morales and Shishkhin, 2002 (Morales PIN 2865/63, PIN 4166/1/2 and Shishkhin 2002; Damiani 2008)

Appendix 3: Data matrix Angusaurus spp. 1110011111 0100111011 1111100010 0010011010 1111100000 010 Benthosuchus sushkini 1100101101 0101110011 0100100011 0011011110 0011000000 010 Calmasuchus acri 0101000?00 11?1?1?101 00001?1011 111????111 0011000000 101 Cherninia denwai 0101100200 1112010000 0000111011 111111111? ?????00101 ?10

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Cyclotosaurus robustus 0102000200 1111001200 1010111111 1111111111 10???10101 000 Edingerella madagascariensis 010010(01)200 1111100000 00001(01)1010 10010?1101 001?011000 000 Eocyclotosaurus spp. 1102101201 0112111001 1110111111 10111111?? ?????10001 012 Eryosuchus garjainovi 010110020(01) 1111011100 0000111011 1111111111 1011000110 100 Lydekkerina huxleyi 0110000100 0101000000 0000100001 0010001010 0011000000 000 Mastodonsaurus giganteus 0101001201 1101011101 1000111111 1111111111 1111000110 010 Odenwaldia heidelbergensis 110010020? ?1110?0??1 ????????1? ??111?11?? ?????00??? ?10 Paracyclotosaurus crooshkanki 0101100200 111201010? 100?111111 1111111111 00?1011111 ?11 Parotosuchus orenburgensis 0100100200 1112010100 0000111011 1111111111 0011000000 110 Procyclotosaurus stantonensis 1102100200 111201100? 0???1??111 ?1111111?? ?????01?01 ?1(12) Quasicyclotosaurus campi 0102101201 0102101001 001011?111 10??0111?? ?????10001 012 Rhineceps nyasaensis 0000000000 0001000000 0000000000 0000000100 0000000000 000 Tatrasuchus wildi 0101?00200 1111000200 0000111011 1111111111 1111010001 100 Thoosuchus yakovlevi 1100011111 0100110011 0111100000 0010011010 1111100000 010 Trematosaurus brauni 1110011111 01001110?1 1111???010 01100?1010 1111100000 010 Stanocephalosaurus birdi 0101000200 1112011000 0001111111 1111111111 0011011001 111 Stanocephalosaurus pronus 0101000200 1112011000 0001111111 1111?11111 00?1011001 011 Uranocentrodon senekalensis 0000000000 0000000000 0000000001 0?00000100 0000000000 000 Vladlenosaurus alexeyevi 1100100200 0110010010 01001?1011 1???????11 ?11?000000 010 Watsonisuchus spp. 0100100200 1112010010 0000111011 1011111111 0011011000 010 Wetlugasaurus angustifrons 010010020(01) 0111010010 0100111011 0101111111 1011000000 010 Xenotosuchus africanus 0101100200 1111011000 0000111011 11?1111111 0011011100 010 Appendix 4: Character−supported nodes Node 1 Ambiguous synapomorphies under DELTRAN.—none Includes Rhineceps nyasaensis + Eocyclotosaurus Ambiguous synapomorphies under ACCTRAN.—5 (0® 1), orbital Unambiguous synapomorphies.—2 (1®0), posterolateral skull cor− margins; 16 (0®1), prefenestral division of the palate; 19 (0®1), ners; 8 (1®0), lacrimal flexure of the infraorbital sensory canal; 12 transvomerine tooth rows; 22 (0®1), cultriform process of the (1®0), the supratemporal; 25 (1®0), crista muscularis of the para− parasphenoid; 29 (0®1), marginal teeth; 34 (0®1), tabular horns; sphenoid; 33 (1®0), posttemporal fenestrae; 37 (1®0), the basi− 36 (0®1), crista muscularis of the parasphenoid; 52 (0®1), skull occipital; 39 (1®0), postglenoid area; 43 (1®0), coronoid series; 44 greatest width−to−midline length ® (1 0), prearticular Remarks.—The narrow and wedge−shaped snout (character 1) found Ambiguous synapomorphies under DELTRAN.—none in Trematosauria is also present in node 8 (Odenwaldia + Vladleno− Ambiguous synapomorphies under ACCTRAN.—none saurus), although this condition was acquired convergently. In addi− Node 2 tion, the lateral line sensory canals, supraorbital sensory canal, and na− Trematosauria + Capitosauria. Includes Benthosuchus sushkini + res (characters 7, 10, and 15, respectively) also distinguish node 18 Eocyclotosaurus (Quasicyclotosaurus + Eocyclotosaurus), possibly reflecting similar Unambiguous synapomorphies.—16 (0®1), prefenestral division environments of these taxa instead of a direct phylogenetic relation− of the palate; 19 (0®1), transvomerine tooth rows; 22 (0®1), ship. ® cultriform process of the parasphenoid; 29 (0 1), marginal teeth; Node 4 36 (0®1), crista muscularis of the parasphenoid; 52 (0®1), skull Trematosauroidea. Includes Thoosuchus yakovlevi + Angusaurus greatest width−to−midline length Unambiguous synapomorphies ® Ambiguous synapomorphies under DELTRAN.—none .—6 (0 1), postorbital–prepineal growth zone; 9 (0®1), occipital sensory canal; 14 (1®0), the Ambiguous synapomorphies under ACCTRAN.—none postorbital; 23 (0®1), cultriform process of the parasphenoid; Remarks.— The clade is well supported by six unambiguous synapo− 24 (0®1), the ectopterygoid; 30 (1®0), ectopterygoid tusks; 38 morphies. The prefenestral division of the palate (character 16) is (1®0), crista falciformis of the squamosal; 41 (0®1), posterior shared by all members of the clade, except node 22 (Cyclotosaurus + Meckelian foramen; 42 (0®1), labial wall of the adductor fossa; 45 Tatrasuchus). In the latter node, the character is reversed. Similarly, (0®1), glenoid fossa transvomerine tooth rows and the cultriform process of the para− sphenoid are reversed in node 9 (Watsonisuchus + Eocyclotosaurus). Ambiguous synapomorphies under DELTRAN.—none ® Node 3 Ambiguous synapomorphies under ACCTRAN.—1 (0 1), snout; 7 ® ® Trematosauria. Includes Benthosuchus sushkini +Angusaurus (0 1), lateral line sensory canals; 10 (0 1), supraorbital sensory canal; 15 (0®1), nares; 20 (0®1), anterior palatal vacuity Unambiguous synapomorphies.—1 (0®1), snout; 7 (0®1), lateral line sensory canals; 10 (0®1), supraorbital sensory canal; 15 (0®1), Node 5 nares; 20 (0®1), anterior palatal vacuity Includes Trematosaurus brauni + Angusaurus FORTUNY ET AL.—NEW CAPITOSAUR FROM SPAIN AND CAPITOSAUR RELATIONSHIPS III

Unambiguous synapomorphies.—3 (0®1), otic notch; 17 (0®1), cyclotosaurus). In this latter node, the frontal is excluded from the occipital condyles orbital margin. On the other hand, the orientation of the trans− Ambiguous synapomorphies under DELTRAN.— none vomerine tooth rows (character 19) and the polarity of the cultri− Ambiguous synapomorphies under ACCTRAN.—5 (1®0), orbital form process of the parasphenoid (character 22) are reversed in margins; 6 (0®1), postorbital–prepineal growth zone; 9 (0®1), oc− comparison with node 2 (Capitosauria + Trematosauria). cipital sensory canal; 14 (1®0), the postorbital; 23 (0®1), cultriform Node 10 process of the parasphenoid; 24 (0®1), the ectopterygoid; 30 (1®0), Includes Edingerella madagascarensis + Eocyclotosaurus ® ® ectopterygoid tusks; 34 (0 1), tabular horns; 38 (1 0), crista falci− Unambiguous synapomorphies.—46 (0®1) Parietal, supratemporal ® formis of the squamosal; 41 (0 1), posterior Meckelian foramen; 42 and postparietal; 47 (0®1) Postparietal, tabular, parietal and supra− ® ® (0 1), labial wall of the adductor fossa; 45 (0 1), glenoid fossa temporal Node 6 Ambiguous synapomorphies under DELTRAN.—none Capitosauria. Includes Wetlugasaurus angustifrons + Eocycloto− Ambiguous synapomorphies under ACCTRAN.—none saurus Remarks.—The condition present in the size relation between pari− Unambiguous synapomorphies.—8 (1®2), lacrimal flexure of the etal, supratemporal and postparietal (character 46) is comparable infraorbital sensory canal; 13 (0®1), preorbital projection of the with node 22 (Cyclotosaurus + Tatrasuchus). ® ® jugal; 26 (0 1), crista muscularis of the parasphenoid; 27 (0 1), Node 11 ® ® “pockets”; 32 (0 1), the quadratojugal; 35 (0 1), oblique ridge of Includes Edingerella madagascarensis + Watsonisuchus the pterygoid; 40 (0®1), hamate process of the prearticular Unambiguous synapomorphies.—32 (1®0), the quadratojugal Ambiguous synapomorphies under DELTRAN.—5 (0®1), orbital Ambiguous synapomorphies under DELTRAN.—none margins; 34 (0®1), tabular horns Ambiguous synapomorphies under ACCTRAN.—none Ambiguous synapomorphies under ACCTRAN.—5 (0®1), orbital margins; 16 (0®1), prefenestral division of the palate; 19 (0®1), Remarks.—The quadratojugal relation with the upper jaw condyle transvomerine tooth rows; 22 (0®1), cultriform process of the (character 32) is reversed, in contrast to the condition found in node 6. parasphenoid; 29 (0®1), marginal teeth; 34 (0®1), tabular horns; Node 12 36 (0®1) crista muscularis of the parasphenoid; 52 (0®1) skull Includes Xenotosuchus africanus + Eocyclotosaurus greatest width−to−midline length Unambiguous synapomorphies.—4 (0®1), tabular horns; 48 (0®1), Remarks.—Seven unambiguous synapomorphies support the capi− interpterygoid vacuities tosaur clade. The lacrimal flexure of the infraorbital sensory canal Ambiguous synapomorphies under DELTRAN.—none (character 8) is absent in most Mesozoic temnospondyls and all Ambiguous synapomorphies under ACCTRAN.—none Palaeozoic temnospondyls in which sensory canals are present Remarks.—The morphology of the tabular horns (character 4) is (Damiani 2001). The lacrimal is step−shaped in groups such as considered an ordered character. Tabular horns are laterally di− lyddekerinds or trematosaurs, in contrast to the typical Z−shaped rected in all members of the clade, except node 17 (Procycloto− morphology in most capitosaurs. The quadratojugal relation with saurus + Eocyclotosaurus). In these cases, the character is also con− Edingerella the upper jaw condyle is reversed in nodes 11 ( + sidered derived because the tabular sutures with the squamosal. On Watsonisuchus Quasicyclotosaurus Eocyclotosaurus ) and 18 ( + ). the other hand, the laterally directed horns were acquired independ− Node 7 ently in node 20 (Calmasuchus + Mastodonsaurus). The derived Includes Odenwaldia heidelbergensis + Eocyclotosaurus condition is also found in Cyclotosaurus, where the tabular contacts Unambiguous synapomorphies.—31 (0®1), denticle field the squamosal. Ambiguous synapomorphies under DELTRAN.—none Node 13 Ambiguous synapomorphies under ACCTRAN.—none Includes Cherninia denwai + Eocyclotosaurus Node 8 Unambiguous synapomorphies.—14 (1®2), the postorbital; 50 Includes Odenwaldia heidelbergensis + Vladlenosaurus alexeyevi (0®1), the squamosal Unambiguous synapomorphies.—1 (0®1), snout Ambiguous synapomorphies under DELTRAN.—none Ambiguous synapomorphies under DELTRAN.—none Ambiguous synapomorphies under ACCTRAN.—none Ambiguous synapomorphies under ACCTRAN.—42 (0®1), labial Remarks.—The postorbital expansion (character 14) is reversed in wall of the adductor fossa. Trematosauroidea (node 4), and the same morphology of the poste− Remarks.—The snout morphology (character 1) is the most similar rior margin of the squamosal (character 50) is also present in node to nodes 3 (Trematosauria) and 4 (Trematosauroidea), possibly re− 22 (Cyclotosaurus + Tatrasuchus). flecting different ecomorphotypes present in the capitosaur clade. Node 14 Node 9 Includes Paracyclotosaurus crookshanki + Eocyclotosaurus ® Includes Watsonisuchus + Eocyclotosaurus Unambiguous synapomorphies.—28 (0 1), the exoccipital; 53 ® Unambiguous synapomorphies.—11 (0®1), the frontal; 19 (1®0), (0 1), postorbital and prefrontal location transvomerine tooth rows; 22 (1®0), cultriform process of the Ambiguous synapomorphies under DELTRAN.—none parasphenoid Ambiguous synapomorphies under ACCTRAN.—none Ambiguous synapomorphies under DELTRAN.—none Node 15 Ambiguous synapomorphies under ACCTRAN.—none Includes Stanocephalosaurus pronus + Eocyclotosaurus Remarks.—The frontal enters medial to the orbit (character 11) in Unambiguous synapomorphies.—17 (0®1), occipital condyles; 48 this node, in clear contrast to node 18 (Quasicyclotosaurus + Eo− (1®0), interpterygoid vacuities

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Ambiguous synapomorphies under DELTRAN.—none cent revised description of Odenwaldia, Schoch (2008) codified this Ambiguous synapomorphies under ACCTRAN.—none character as missing data. He did not find a clear relationship between Remarks.—The placement of the occipital condyles in this node is these taxa. In the present analysis, the addition of Vladlenosaurus pro− similar to node 4 (Trematosauroidea). The polarity of the inter− vides new light to this discussion. In the Russian taxa, the frontal is pterygoid vacuities is reversed in contrast to node 12 (Xenotosuchus clearly excluded from the orbital margins. Nevertheless, our cladistic + Eocyclotosaurus). analysis reveals the relationship between Odenwaldia and Vladleno− saurus. In contrast, any relationship can be assessed with Eocycloto− Node 16 saurus or Quasicyclotosaurus. Includes Stanocephalosaurus pronus + Stanocephalosaurus birdi Unambiguous synapomorphies.—5 (1®0), orbital margins; 24 Node 19 (0®1), the ectopterygoid Includes Parotosuchus orenburgensis + Mastodonsaurus giganteus Ambiguous synapomorphies under DELTRAN.—none Unambiguous synapomorphies.—18 (0®1), choanal outline; 51 Ambiguous synapomorphies under ACCTRAN.—none (0®1), postglenoid area outgrowth Remarks.—The condition of the orbital margins (character 5) is re− Ambiguous synapomorphies under DELTRAN.—none versed in this node. The same polarity is present in node 20 (Calma− Ambiguous synapomorphies under ACCTRAN.—none suchus + Mastodonsaurus). Otherwise, the ectopterygoid is similar Node 20 to that in node 4 (Trematosauroidea). Includes Calmasuchus acri + Mastodonsaurus giganteus Node 17 Unambiguous synapomorphies.—4 (0®1), tabular horns; 5 (1®0), Includes Procyclotosaurus stantonensis + Eocyclotosaurus orbital margins; 52 (0®1), skull greatest width−to−midline length Unambiguous synapomorphies.—4 (1®2), tabular horns Ambiguous synapomorphies under DELTRAN.—none Ambiguous synapomorphies under DELTRAN.—none Ambiguous synapomorphies under ACCTRAN.—17 (0®1), occip− Ambiguous synapomorphies under ACCTRAN.—1 (0®1), snout; ital condyles ® ® 20 (0 1), anterior palatal vacuity; 23 (0 1), cultriform process of Remarks.—The tabular horns (character 4) are laterally directed in the ® the parasphenoid; 53 (1 2), postorbital and prefrontal location members of this node, as previously discussed for node 12 (Xenoto− Remarks.—As previously discussed, the tabular horn in this node suchus + Eocyclotosaurus). Cyclotosaurus is the unique member of contacts the squamosal, resulting in an embayment. This morphol− this node displaying the tabular in contact with the squamosal. The ogy is shared with the genus Cyclotosaurus. Our analysis suggests condition of the orbital margins (character 5) is reversed. that this morphology was acquired independently in the two nodes. Node 21 Node 18 Includes Cyclotosaurus robustus + Mastodonsaurus giganteus Includes Quasicyclotosaurus campi + Eocyclotosaurus Unambiguous synapomorphies.—41 (0®1), posterior Meckelian Unambiguous synapomorphies.—7 (0®1), lateral line sensory ca− foramen ® ® nals; 10 (0 1), supraorbital sensory canal; 11 (1 0), the frontal; Ambiguous synapomorphies under DELTRAN.—none 15 (0®1), nares; 32 (1®0), the quadratojugal; 47 (1®0), the Ambiguous synapomorphies under ACCTRAN.—48 (0®1), inter− postparietal, tabular, parietal, and supraparietal pterygoid vacuities Ambiguous synapomorphies under DELTRAN.—20 (0®1), ante− Remarks rior palatal vacuity; 23 (0®1), cultriform process of the para− .—The posterior Meckelian foramen is elongated and com− sphenoid; 53 (1®2), postorbital and prefrontal location parable to that of trematosaurs, possibly reflecting higher adductor musculature in these taxa, instead of a phylogenetic relationship. Ambiguous synapomorphies under ACCTRAN.—none Remarks.—The lateral line sensory canals (character 7) are continu− Node 22 ous and well impressed in this node. Most capitosaurs show discontin− Includes Cyclotosaurus robustus + Tatrasuchus wildi uous and weak−impressed lateral lines. The condition present in this Unambiguous synapomorphies.—16 (1®0), prefenestral division node is similar to that of nodes 3 (Trematosauria) and 4 (Tremato− of the palate; 18 (1®2), choanal outline; 46 (0®1), the parietal, sauroidea). On the other hand, the same polarity of the supraorbital supratemporal, and postparietal; 50 (0®1), the squamosal sensory canal (character 10) is also shared by nodes 3 (Tremato− Ambiguous synapomorphies under DELTRAN.—none sauria), 4 (Trematosauroidea), 18 (Quasicyclotosaurus + Eocycloto− Ambiguous synapomorphies under ACCTRAN.—none saurus),and23(Eryosuchus + Mastodonsaurus). Although the phy− Remarks.—The prefenestral division of the palate (character 16) is re− logenetic analysis revealed the character as significant, the high de− versed. The choanal outline (character 18) is slit−like in the members gree of plasticity of this character is attributable to its intraspecific of node 19 (Parotosuchus + Mastodonsaurus), evolving to circular or variation (see Damiani 2001 for further details). The polarity of the subcircular morphology in this node (Cyclotosaurus + Tatrasuchus). frontal, quadratojugal, and postparietal, tabular, parietal, and supra− The condition found at the posterior margin of the squamosal is also parietal characters (characters 11, 32, and 47, respectively) are re− present in node 13 (Cherninia + Eocyclotosaurus). versed. The morphology of the nares (character 15) is similar to that of Node 23 nodes 3 (Trematosauria) and 4 (Trematosauroidea). The evolution of the frontal bone in relation to the orbit (character 11) needs a com− Includes Eryosuchus garjainovi + Mastodonsaurus giganteus ment. Damiani (2001) considered that the frontal bone was excluded Unambiguous synapomorphies.—49 (0®1), the parasphenoid from the orbital margin in Odenwaldia. This is the same condition Ambiguous synapomorphies under DELTRAN.—17 (0®1), the oc− present in Eocyclotosaurus and Quasicyclotosaurus,andwasdis− cipital condyles; 48 (0®1), the interpterygoid vacuities cussed by the author as one of the key characters to infer a relationship Ambiguous synapomorphies under ACCTRAN.—10 (0®1), the between Odenwaldia and Eocyclotosaurus. Nevertheless, in the re− supraorbital sensory canal